user)
In addition to the usages of the user channel keyword
discussed in the PMDF System Manager's Guide , this keyword also has a special meaning
for BITNET channels.
Messages sent via BITNET are tagged with the name of the user and system that sent the message. If someone on the local system sent the message, PMDF uses that user's username as the user part of the tag. The following section explains how this can be inhibited if desired. PMDF uses "MAILER" as the default user part of the tag for messages originating on remote systems. This works correctly in most cases, but some NJE mail systems (notably many of those on BITNET) are somewhat paranoid and check tag information to make sure the message was relayed by a "trusted" user on a "trusted" mail system. The name of this special, trusted user is usually, but not always, the same as the name of the special mailbox associated with any local Jnet or ANJE gateway that has been set up.
Trusted mail systems typically are registered with some type of central network administration. PMDF itself does not provide facilities for restricting access to trusted systems. However, PMDF does provide the means to set the username tag to a value that is acceptable to remote mailers.
The user keyword is used to tell the Jnet and ANJE master
programs to use an alternate username in the tag field. The actual
username to use in the tag should appear directly after the
user keyword.
If no user keyword appears on the channel associated with
an outgoing message, PMDF then checks to see if the user
keyword has been specified on the local channel, and if it has, uses
the value associated with that specification. This makes it possible to
simplify some configurations that have user keywords on
many or even all of the bit_ channels.
The example channel block shown in Section 2.0.1 uses the
user keyword to set the username associated with the
:mailer. tag entry in the node's BITNIC node registration.